// Copyright 2009-2012 by contributors, MIT License
// vim: ts=4 sts=4 sw=4 expandtab

// Module systems magic dance
(function (definition) {
	// RequireJS
	if (typeof define == "function") {
		define(definition);
		// YUI3
	} else if (typeof YUI == "function") {
		YUI.add("es5", definition);
		// CommonJS and <script>
	} else {
		definition();
	}
})(function () {

	/**
	 * Brings an environment as close to ECMAScript 5 compliance
	 * as is possible with the facilities of erstwhile engines.
	 *
	 * Annotated ES5: http://es5.github.com/ (specific links below)
	 * ES5 Spec: http://www.ecma-international.org/publications/files/ECMA-ST/Ecma-262.pdf
	 * Required reading: http://javascriptweblog.wordpress.com/2011/12/05/extending-javascript-natives/
	 */

//
// Function
// ========
//

// ES-5 15.3.4.5
// http://es5.github.com/#x15.3.4.5

	function Empty() {}

	if (!Function.prototype.bind) {
		Function.prototype.bind = function bind(that) { // .length is 1
			// 1. Let Target be the this value.
			var target = this;
			// 2. If IsCallable(Target) is false, throw a TypeError exception.
			if (typeof target != "function") {
				throw new TypeError("Function.prototype.bind called on incompatible " + target);
			}
			// 3. Let A be a new (possibly empty) internal list of all of the
			//   argument values provided after thisArg (arg1, arg2 etc), in order.
			// XXX slicedArgs will stand in for "A" if used
			var args = _Array_slice_.call(arguments, 1); // for normal call
			// 4. Let F be a new native ECMAScript object.
			// 11. Set the [[Prototype]] internal property of F to the standard
			//   built-in Function prototype object as specified in 15.3.3.1.
			// 12. Set the [[Call]] internal property of F as described in
			//   15.3.4.5.1.
			// 13. Set the [[Construct]] internal property of F as described in
			//   15.3.4.5.2.
			// 14. Set the [[HasInstance]] internal property of F as described in
			//   15.3.4.5.3.
			var bound = function () {

				if (this instanceof bound) {
					// 15.3.4.5.2 [[Construct]]
					// When the [[Construct]] internal method of a function object,
					// F that was created using the bind function is called with a
					// list of arguments ExtraArgs, the following steps are taken:
					// 1. Let target be the value of F's [[TargetFunction]]
					//   internal property.
					// 2. If target has no [[Construct]] internal method, a
					//   TypeError exception is thrown.
					// 3. Let boundArgs be the value of F's [[BoundArgs]] internal
					//   property.
					// 4. Let args be a new list containing the same values as the
					//   list boundArgs in the same order followed by the same
					//   values as the list ExtraArgs in the same order.
					// 5. Return the result of calling the [[Construct]] internal
					//   method of target providing args as the arguments.

					var result = target.apply(
						this,
						args.concat(_Array_slice_.call(arguments))
					);
					if (Object(result) === result) {
						return result;
					}
					return this;

				} else {
					// 15.3.4.5.1 [[Call]]
					// When the [[Call]] internal method of a function object, F,
					// which was created using the bind function is called with a
					// this value and a list of arguments ExtraArgs, the following
					// steps are taken:
					// 1. Let boundArgs be the value of F's [[BoundArgs]] internal
					//   property.
					// 2. Let boundThis be the value of F's [[BoundThis]] internal
					//   property.
					// 3. Let target be the value of F's [[TargetFunction]] internal
					//   property.
					// 4. Let args be a new list containing the same values as the
					//   list boundArgs in the same order followed by the same
					//   values as the list ExtraArgs in the same order.
					// 5. Return the result of calling the [[Call]] internal method
					//   of target providing boundThis as the this value and
					//   providing args as the arguments.

					// equiv: target.call(this, ...boundArgs, ...args)
					return target.apply(
						that,
						args.concat(_Array_slice_.call(arguments))
					);

				}

			};
			if(target.prototype) {
				Empty.prototype = target.prototype;
				bound.prototype = new Empty();
				// Clean up dangling references.
				Empty.prototype = null;
			}
			// XXX bound.length is never writable, so don't even try
			//
			// 15. If the [[Class]] internal property of Target is "Function", then
			//     a. Let L be the length property of Target minus the length of A.
			//     b. Set the length own property of F to either 0 or L, whichever is
			//       larger.
			// 16. Else set the length own property of F to 0.
			// 17. Set the attributes of the length own property of F to the values
			//   specified in 15.3.5.1.

			// TODO
			// 18. Set the [[Extensible]] internal property of F to true.

			// TODO
			// 19. Let thrower be the [[ThrowTypeError]] function Object (13.2.3).
			// 20. Call the [[DefineOwnProperty]] internal method of F with
			//   arguments "caller", PropertyDescriptor {[[Get]]: thrower, [[Set]]:
			//   thrower, [[Enumerable]]: false, [[Configurable]]: false}, and
			//   false.
			// 21. Call the [[DefineOwnProperty]] internal method of F with
			//   arguments "arguments", PropertyDescriptor {[[Get]]: thrower,
			//   [[Set]]: thrower, [[Enumerable]]: false, [[Configurable]]: false},
			//   and false.

			// TODO
			// NOTE Function objects created using Function.prototype.bind do not
			// have a prototype property or the [[Code]], [[FormalParameters]], and
			// [[Scope]] internal properties.
			// XXX can't delete prototype in pure-js.

			// 22. Return F.
			return bound;
		};
	}

// Shortcut to an often accessed properties, in order to avoid multiple
// dereference that costs universally.
// _Please note: Shortcuts are defined after `Function.prototype.bind` as we
// us it in defining shortcuts.
	var call = Function.prototype.call;
	var prototypeOfArray = Array.prototype;
	var prototypeOfObject = Object.prototype;
	var _Array_slice_ = prototypeOfArray.slice;
// Having a toString local variable name breaks in Opera so use _toString.
	var _toString = call.bind(prototypeOfObject.toString);
	var owns = call.bind(prototypeOfObject.hasOwnProperty);

// If JS engine supports accessors creating shortcuts.
	var defineGetter;
	var defineSetter;
	var lookupGetter;
	var lookupSetter;
	var supportsAccessors;
	if ((supportsAccessors = owns(prototypeOfObject, "__defineGetter__"))) {
		defineGetter = call.bind(prototypeOfObject.__defineGetter__);
		defineSetter = call.bind(prototypeOfObject.__defineSetter__);
		lookupGetter = call.bind(prototypeOfObject.__lookupGetter__);
		lookupSetter = call.bind(prototypeOfObject.__lookupSetter__);
	}

//
// Array
// =====
//

// ES5 15.4.4.12
// http://es5.github.com/#x15.4.4.12
// Default value for second param
// [bugfix, ielt9, old browsers]
// IE < 9 bug: [1,2].splice(0).join("") == "" but should be "12"
	if ([1,2].splice(0).length != 2) {
		var array_splice = Array.prototype.splice;

		if(function() { // test IE < 9 to splice bug - see issue #138
			function makeArray(l) {
				var a = [];
				while (l--) {
					a.unshift(l)
				}
				return a
			}

			var array = []
				, lengthBefore
				;

			array.splice.bind(array, 0, 0).apply(null, makeArray(20));
			array.splice.bind(array, 0, 0).apply(null, makeArray(26));

			lengthBefore = array.length; //20
			array.splice(5, 0, "XXX"); // add one element

			if(lengthBefore + 1 == array.length) {
				return true;// has right splice implementation without bugs
			}
			// else {
			//    IE8 bug
			// }
		}()) {//IE 6/7
			Array.prototype.splice = function(start, deleteCount) {
				if (!arguments.length) {
					return [];
				} else {
					return array_splice.apply(this, [
						start === void 0 ? 0 : start,
						deleteCount === void 0 ? (this.length - start) : deleteCount
					].concat(_Array_slice_.call(arguments, 2)))
				}
			};
		}
		else {//IE8
			Array.prototype.splice = function(start, deleteCount) {
				var result
					, args = _Array_slice_.call(arguments, 2)
					, addElementsCount = args.length
					;

				if(!arguments.length) {
					return [];
				}

				if(start === void 0) { // default
					start = 0;
				}
				if(deleteCount === void 0) { // default
					deleteCount = this.length - start;
				}

				if(addElementsCount > 0) {
					if(deleteCount <= 0) {
						if(start == this.length) { // tiny optimisation #1
							this.push.apply(this, args);
							return [];
						}

						if(start == 0) { // tiny optimisation #2
							this.unshift.apply(this, args);
							return [];
						}
					}

					// Array.prototype.splice implementation
					result = _Array_slice_.call(this, start, start + deleteCount);// delete part
					args.push.apply(args, _Array_slice_.call(this, start + deleteCount, this.length));// right part
					args.unshift.apply(args, _Array_slice_.call(this, 0, start));// left part

					// delete all items from this array and replace it to 'left part' + _Array_slice_.call(arguments, 2) + 'right part'
					args.unshift(0, this.length);

					array_splice.apply(this, args);

					return result;
				}

				return array_splice.call(this, start, deleteCount);
			}

		}
	}

// ES5 15.4.4.12
// http://es5.github.com/#x15.4.4.13
// Return len+argCount.
// [bugfix, ielt8]
// IE < 8 bug: [].unshift(0) == undefined but should be "1"
	if ([].unshift(0) != 1) {
		var array_unshift = Array.prototype.unshift;
		Array.prototype.unshift = function() {
			array_unshift.apply(this, arguments);
			return this.length;
		};
	}

// ES5 15.4.3.2
// http://es5.github.com/#x15.4.3.2
// https://developer.mozilla.org/en/JavaScript/Reference/Global_Objects/Array/isArray
	if (!Array.isArray) {
		Array.isArray = function isArray(obj) {
			return _toString(obj) == "[object Array]";
		};
	}

// The IsCallable() check in the Array functions
// has been replaced with a strict check on the
// internal class of the object to trap cases where
// the provided function was actually a regular
// expression literal, which in V8 and
// JavaScriptCore is a typeof "function".  Only in
// V8 are regular expression literals permitted as
// reduce parameters, so it is desirable in the
// general case for the shim to match the more
// strict and common behavior of rejecting regular
// expressions.

// ES5 15.4.4.18
// http://es5.github.com/#x15.4.4.18
// https://developer.mozilla.org/en/JavaScript/Reference/Global_Objects/array/forEach

// Check failure of by-index access of string characters (IE < 9)
// and failure of `0 in boxedString` (Rhino)
	var boxedString = Object("a"),
		splitString = boxedString[0] != "a" || !(0 in boxedString);

	if (!Array.prototype.forEach) {
		Array.prototype.forEach = function forEach(fun /*, thisp*/) {
			var object = toObject(this),
				self = splitString && _toString(this) == "[object String]" ?
					this.split("") :
					object,
				thisp = arguments[1],
				i = -1,
				length = self.length >>> 0;

			// If no callback function or if callback is not a callable function
			if (_toString(fun) != "[object Function]") {
				throw new TypeError(); // TODO message
			}

			while (++i < length) {
				if (i in self) {
					// Invoke the callback function with call, passing arguments:
					// context, property value, property key, thisArg object
					// context
					fun.call(thisp, self[i], i, object);
				}
			}
		};
	}

// ES5 15.4.4.19
// http://es5.github.com/#x15.4.4.19
// https://developer.mozilla.org/en/Core_JavaScript_1.5_Reference/Objects/Array/map
	if (!Array.prototype.map) {
		Array.prototype.map = function map(fun /*, thisp*/) {
			var object = toObject(this),
				self = splitString && _toString(this) == "[object String]" ?
					this.split("") :
					object,
				length = self.length >>> 0,
				result = Array(length),
				thisp = arguments[1];

			// If no callback function or if callback is not a callable function
			if (_toString(fun) != "[object Function]") {
				throw new TypeError(fun + " is not a function");
			}

			for (var i = 0; i < length; i++) {
				if (i in self)
					result[i] = fun.call(thisp, self[i], i, object);
			}
			return result;
		};
	}

// ES5 15.4.4.20
// http://es5.github.com/#x15.4.4.20
// https://developer.mozilla.org/en/Core_JavaScript_1.5_Reference/Objects/Array/filter
	if (!Array.prototype.filter) {
		Array.prototype.filter = function filter(fun /*, thisp */) {
			var object = toObject(this),
				self = splitString && _toString(this) == "[object String]" ?
					this.split("") :
					object,
				length = self.length >>> 0,
				result = [],
				value,
				thisp = arguments[1];

			// If no callback function or if callback is not a callable function
			if (_toString(fun) != "[object Function]") {
				throw new TypeError(fun + " is not a function");
			}

			for (var i = 0; i < length; i++) {
				if (i in self) {
					value = self[i];
					if (fun.call(thisp, value, i, object)) {
						result.push(value);
					}
				}
			}
			return result;
		};
	}

// ES5 15.4.4.16
// http://es5.github.com/#x15.4.4.16
// https://developer.mozilla.org/en/JavaScript/Reference/Global_Objects/Array/every
	if (!Array.prototype.every) {
		Array.prototype.every = function every(fun /*, thisp */) {
			var object = toObject(this),
				self = splitString && _toString(this) == "[object String]" ?
					this.split("") :
					object,
				length = self.length >>> 0,
				thisp = arguments[1];

			// If no callback function or if callback is not a callable function
			if (_toString(fun) != "[object Function]") {
				throw new TypeError(fun + " is not a function");
			}

			for (var i = 0; i < length; i++) {
				if (i in self && !fun.call(thisp, self[i], i, object)) {
					return false;
				}
			}
			return true;
		};
	}

// ES5 15.4.4.17
// http://es5.github.com/#x15.4.4.17
// https://developer.mozilla.org/en/JavaScript/Reference/Global_Objects/Array/some
	if (!Array.prototype.some) {
		Array.prototype.some = function some(fun /*, thisp */) {
			var object = toObject(this),
				self = splitString && _toString(this) == "[object String]" ?
					this.split("") :
					object,
				length = self.length >>> 0,
				thisp = arguments[1];

			// If no callback function or if callback is not a callable function
			if (_toString(fun) != "[object Function]") {
				throw new TypeError(fun + " is not a function");
			}

			for (var i = 0; i < length; i++) {
				if (i in self && fun.call(thisp, self[i], i, object)) {
					return true;
				}
			}
			return false;
		};
	}

// ES5 15.4.4.21
// http://es5.github.com/#x15.4.4.21
// https://developer.mozilla.org/en/Core_JavaScript_1.5_Reference/Objects/Array/reduce
	if (!Array.prototype.reduce) {
		Array.prototype.reduce = function reduce(fun /*, initial*/) {
			var object = toObject(this),
				self = splitString && _toString(this) == "[object String]" ?
					this.split("") :
					object,
				length = self.length >>> 0;

			// If no callback function or if callback is not a callable function
			if (_toString(fun) != "[object Function]") {
				throw new TypeError(fun + " is not a function");
			}

			// no value to return if no initial value and an empty array
			if (!length && arguments.length == 1) {
				throw new TypeError("reduce of empty array with no initial value");
			}

			var i = 0;
			var result;
			if (arguments.length >= 2) {
				result = arguments[1];
			} else {
				do {
					if (i in self) {
						result = self[i++];
						break;
					}

					// if array contains no values, no initial value to return
					if (++i >= length) {
						throw new TypeError("reduce of empty array with no initial value");
					}
				} while (true);
			}

			for (; i < length; i++) {
				if (i in self) {
					result = fun.call(void 0, result, self[i], i, object);
				}
			}

			return result;
		};
	}

// ES5 15.4.4.22
// http://es5.github.com/#x15.4.4.22
// https://developer.mozilla.org/en/Core_JavaScript_1.5_Reference/Objects/Array/reduceRight
	if (!Array.prototype.reduceRight) {
		Array.prototype.reduceRight = function reduceRight(fun /*, initial*/) {
			var object = toObject(this),
				self = splitString && _toString(this) == "[object String]" ?
					this.split("") :
					object,
				length = self.length >>> 0;

			// If no callback function or if callback is not a callable function
			if (_toString(fun) != "[object Function]") {
				throw new TypeError(fun + " is not a function");
			}

			// no value to return if no initial value, empty array
			if (!length && arguments.length == 1) {
				throw new TypeError("reduceRight of empty array with no initial value");
			}

			var result, i = length - 1;
			if (arguments.length >= 2) {
				result = arguments[1];
			} else {
				do {
					if (i in self) {
						result = self[i--];
						break;
					}

					// if array contains no values, no initial value to return
					if (--i < 0) {
						throw new TypeError("reduceRight of empty array with no initial value");
					}
				} while (true);
			}

			do {
				if (i in this) {
					result = fun.call(void 0, result, self[i], i, object);
				}
			} while (i--);

			return result;
		};
	}

// ES5 15.4.4.14
// http://es5.github.com/#x15.4.4.14
// https://developer.mozilla.org/en/JavaScript/Reference/Global_Objects/Array/indexOf
	if (!Array.prototype.indexOf || ([0, 1].indexOf(1, 2) != -1)) {
		Array.prototype.indexOf = function indexOf(sought /*, fromIndex */ ) {
			var self = splitString && _toString(this) == "[object String]" ?
					this.split("") :
					toObject(this),
				length = self.length >>> 0;

			if (!length) {
				return -1;
			}

			var i = 0;
			if (arguments.length > 1) {
				i = toInteger(arguments[1]);
			}

			// handle negative indices
			i = i >= 0 ? i : Math.max(0, length + i);
			for (; i < length; i++) {
				if (i in self && self[i] === sought) {
					return i;
				}
			}
			return -1;
		};
	}

// ES5 15.4.4.15
// http://es5.github.com/#x15.4.4.15
// https://developer.mozilla.org/en/JavaScript/Reference/Global_Objects/Array/lastIndexOf
	if (!Array.prototype.lastIndexOf || ([0, 1].lastIndexOf(0, -3) != -1)) {
		Array.prototype.lastIndexOf = function lastIndexOf(sought /*, fromIndex */) {
			var self = splitString && _toString(this) == "[object String]" ?
					this.split("") :
					toObject(this),
				length = self.length >>> 0;

			if (!length) {
				return -1;
			}
			var i = length - 1;
			if (arguments.length > 1) {
				i = Math.min(i, toInteger(arguments[1]));
			}
			// handle negative indices
			i = i >= 0 ? i : length - Math.abs(i);
			for (; i >= 0; i--) {
				if (i in self && sought === self[i]) {
					return i;
				}
			}
			return -1;
		};
	}

//
// Object
// ======
//

// ES5 15.2.3.14
// http://es5.github.com/#x15.2.3.14
	if (!Object.keys) {
		// http://whattheheadsaid.com/2010/10/a-safer-object-keys-compatibility-implementation
		var hasDontEnumBug = true,
			dontEnums = [
				"toString",
				"toLocaleString",
				"valueOf",
				"hasOwnProperty",
				"isPrototypeOf",
				"propertyIsEnumerable",
				"constructor"
			],
			dontEnumsLength = dontEnums.length;

		for (var key in {"toString": null}) {
			hasDontEnumBug = false;
		}

		Object.keys = function keys(object) {

			if (
				(typeof object != "object" && typeof object != "function") ||
					object === null
				) {
				throw new TypeError("Object.keys called on a non-object");
			}

			var keys = [];
			for (var name in object) {
				if (owns(object, name)) {
					keys.push(name);
				}
			}

			if (hasDontEnumBug) {
				for (var i = 0, ii = dontEnumsLength; i < ii; i++) {
					var dontEnum = dontEnums[i];
					if (owns(object, dontEnum)) {
						keys.push(dontEnum);
					}
				}
			}
			return keys;
		};

	}

//
// Date
// ====
//

// ES5 15.9.5.43
// http://es5.github.com/#x15.9.5.43
// This function returns a String value represent the instance in time
// represented by this Date object. The format of the String is the Date Time
// string format defined in 15.9.1.15. All fields are present in the String.
// The time zone is always UTC, denoted by the suffix Z. If the time value of
// this object is not a finite Number a RangeError exception is thrown.
	var negativeDate = -62198755200000,
		negativeYearString = "-000001";
	if (
		!Date.prototype.toISOString ||
			(new Date(negativeDate).toISOString().indexOf(negativeYearString) === -1)
		) {
		Date.prototype.toISOString = function toISOString() {
			var result, length, value, year, month;
			if (!isFinite(this)) {
				throw new RangeError("Date.prototype.toISOString called on non-finite value.");
			}

			year = this.getUTCFullYear();

			month = this.getUTCMonth();
			// see https://github.com/kriskowal/es5-shim/issues/111
			year += Math.floor(month / 12);
			month = (month % 12 + 12) % 12;

			// the date time string format is specified in 15.9.1.15.
			result = [month + 1, this.getUTCDate(),
				this.getUTCHours(), this.getUTCMinutes(), this.getUTCSeconds()];
			year = (
				(year < 0 ? "-" : (year > 9999 ? "+" : "")) +
					("00000" + Math.abs(year))
						.slice(0 <= year && year <= 9999 ? -4 : -6)
				);

			length = result.length;
			while (length--) {
				value = result[length];
				// pad months, days, hours, minutes, and seconds to have two
				// digits.
				if (value < 10) {
					result[length] = "0" + value;
				}
			}
			// pad milliseconds to have three digits.
			return (
				year + "-" + result.slice(0, 2).join("-") +
					"T" + result.slice(2).join(":") + "." +
					("000" + this.getUTCMilliseconds()).slice(-3) + "Z"
				);
		};
	}


// ES5 15.9.5.44
// http://es5.github.com/#x15.9.5.44
// This function provides a String representation of a Date object for use by
// JSON.stringify (15.12.3).
	var dateToJSONIsSupported = false;
	try {
		dateToJSONIsSupported = (
			Date.prototype.toJSON &&
				new Date(NaN).toJSON() === null &&
				new Date(negativeDate).toJSON().indexOf(negativeYearString) !== -1 &&
				Date.prototype.toJSON.call({ // generic
					toISOString: function () {
						return true;
					}
				})
			);
	} catch (e) {
	}
	if (!dateToJSONIsSupported) {
		Date.prototype.toJSON = function toJSON(key) {
			// When the toJSON method is called with argument key, the following
			// steps are taken:

			// 1.  Let O be the result of calling ToObject, giving it the this
			// value as its argument.
			// 2. Let tv be toPrimitive(O, hint Number).
			var o = Object(this),
				tv = toPrimitive(o),
				toISO;
			// 3. If tv is a Number and is not finite, return null.
			if (typeof tv === "number" && !isFinite(tv)) {
				return null;
			}
			// 4. Let toISO be the result of calling the [[Get]] internal method of
			// O with argument "toISOString".
			toISO = o.toISOString;
			// 5. If IsCallable(toISO) is false, throw a TypeError exception.
			if (typeof toISO != "function") {
				throw new TypeError("toISOString property is not callable");
			}
			// 6. Return the result of calling the [[Call]] internal method of
			//  toISO with O as the this value and an empty argument list.
			return toISO.call(o);

			// NOTE 1 The argument is ignored.

			// NOTE 2 The toJSON function is intentionally generic; it does not
			// require that its this value be a Date object. Therefore, it can be
			// transferred to other kinds of objects for use as a method. However,
			// it does require that any such object have a toISOString method. An
			// object is free to use the argument key to filter its
			// stringification.
		};
	}

// ES5 15.9.4.2
// http://es5.github.com/#x15.9.4.2
// based on work shared by Daniel Friesen (dantman)
// http://gist.github.com/303249
	if (!Date.parse || "Date.parse is buggy") {
		// XXX global assignment won't work in embeddings that use
		// an alternate object for the context.
		Date = (function(NativeDate) {

			// Date.length === 7
			function Date(Y, M, D, h, m, s, ms) {
				var length = arguments.length;
				if (this instanceof NativeDate) {
					var date = length == 1 && String(Y) === Y ? // isString(Y)
						// We explicitly pass it through parse:
						new NativeDate(Date.parse(Y)) :
						// We have to manually make calls depending on argument
						// length here
						length >= 7 ? new NativeDate(Y, M, D, h, m, s, ms) :
							length >= 6 ? new NativeDate(Y, M, D, h, m, s) :
								length >= 5 ? new NativeDate(Y, M, D, h, m) :
									length >= 4 ? new NativeDate(Y, M, D, h) :
										length >= 3 ? new NativeDate(Y, M, D) :
											length >= 2 ? new NativeDate(Y, M) :
												length >= 1 ? new NativeDate(Y) :
													new NativeDate();
					// Prevent mixups with unfixed Date object
					date.constructor = Date;
					return date;
				}
				return NativeDate.apply(this, arguments);
			};

			// 15.9.1.15 Date Time String Format.
			var isoDateExpression = new RegExp("^" +
				"(\\d{4}|[\+\-]\\d{6})" + // four-digit year capture or sign +
				// 6-digit extended year
				"(?:-(\\d{2})" + // optional month capture
				"(?:-(\\d{2})" + // optional day capture
				"(?:" + // capture hours:minutes:seconds.milliseconds
				"T(\\d{2})" + // hours capture
				":(\\d{2})" + // minutes capture
				"(?:" + // optional :seconds.milliseconds
				":(\\d{2})" + // seconds capture
				"(?:(\\.\\d{1,}))?" + // milliseconds capture
				")?" +
				"(" + // capture UTC offset component
				"Z|" + // UTC capture
				"(?:" + // offset specifier +/-hours:minutes
				"([-+])" + // sign capture
				"(\\d{2})" + // hours offset capture
				":(\\d{2})" + // minutes offset capture
				")" +
				")?)?)?)?" +
				"$");

			var months = [
				0, 31, 59, 90, 120, 151, 181, 212, 243, 273, 304, 334, 365
			];

			function dayFromMonth(year, month) {
				var t = month > 1 ? 1 : 0;
				return (
					months[month] +
						Math.floor((year - 1969 + t) / 4) -
						Math.floor((year - 1901 + t) / 100) +
						Math.floor((year - 1601 + t) / 400) +
						365 * (year - 1970)
					);
			}

			// Copy any custom methods a 3rd party library may have added
			for (var key in NativeDate) {
				Date[key] = NativeDate[key];
			}

			// Copy "native" methods explicitly; they may be non-enumerable
			Date.now = NativeDate.now;
			Date.UTC = NativeDate.UTC;
			Date.prototype = NativeDate.prototype;
			Date.prototype.constructor = Date;

			// Upgrade Date.parse to handle simplified ISO 8601 strings
			Date.parse = function parse(string) {
				var match = isoDateExpression.exec(string);
				if (match) {
					// parse months, days, hours, minutes, seconds, and milliseconds
					// provide default values if necessary
					// parse the UTC offset component
					var year = Number(match[1]),
						month = Number(match[2] || 1) - 1,
						day = Number(match[3] || 1) - 1,
						hour = Number(match[4] || 0),
						minute = Number(match[5] || 0),
						second = Number(match[6] || 0),
						millisecond = Math.floor(Number(match[7] || 0) * 1000),
					// When time zone is missed, local offset should be used
					// (ES 5.1 bug)
					// see https://bugs.ecmascript.org/show_bug.cgi?id=112
						offset = !match[4] || match[8] ?
							0 : Number(new NativeDate(1970, 0)),
						signOffset = match[9] === "-" ? 1 : -1,
						hourOffset = Number(match[10] || 0),
						minuteOffset = Number(match[11] || 0),
						result;
					if (
						hour < (
							minute > 0 || second > 0 || millisecond > 0 ?
								24 : 25
							) &&
							minute < 60 && second < 60 && millisecond < 1000 &&
							month > -1 && month < 12 && hourOffset < 24 &&
							minuteOffset < 60 && // detect invalid offsets
							day > -1 &&
							day < (
								dayFromMonth(year, month + 1) -
									dayFromMonth(year, month)
								)
						) {
						result = (
							(dayFromMonth(year, month) + day) * 24 +
								hour +
								hourOffset * signOffset
							) * 60;
						result = (
							(result + minute + minuteOffset * signOffset) * 60 +
								second
							) * 1000 + millisecond + offset;
						if (-8.64e15 <= result && result <= 8.64e15) {
							return result;
						}
					}
					return NaN;
				}
				return NativeDate.parse.apply(this, arguments);
			};

			return Date;
		})(Date);
	}

// ES5 15.9.4.4
// http://es5.github.com/#x15.9.4.4
	if (!Date.now) {
		Date.now = function now() {
			return new Date().getTime();
		};
	}


//
// Number
// ======
//

// ES5.1 15.7.4.5
// http://es5.github.com/#x15.7.4.5
	if (!Number.prototype.toFixed || (0.00008).toFixed(3) !== '0.000' || (0.9).toFixed(0) === '0' || (1.255).toFixed(2) !== '1.25' || (1000000000000000128).toFixed(0) !== "1000000000000000128") {
		// Hide these variables and functions
		(function () {
			var base, size, data, i;

			base = 1e7;
			size = 6;
			data = [0, 0, 0, 0, 0, 0];

			function multiply(n, c) {
				var i = -1;
				while (++i < size) {
					c += n * data[i];
					data[i] = c % base;
					c = Math.floor(c / base);
				}
			}

			function divide(n) {
				var i = size, c = 0;
				while (--i >= 0) {
					c += data[i];
					data[i] = Math.floor(c / n);
					c = (c % n) * base;
				}
			}

			function toString() {
				var i = size;
				var s = '';
				while (--i >= 0) {
					if (s !== '' || i === 0 || data[i] !== 0) {
						var t = String(data[i]);
						if (s === '') {
							s = t;
						} else {
							s += '0000000'.slice(0, 7 - t.length) + t;
						}
					}
				}
				return s;
			}

			function pow(x, n, acc) {
				return (n === 0 ? acc : (n % 2 === 1 ? pow(x, n - 1, acc * x) : pow(x * x, n / 2, acc)));
			}

			function log(x) {
				var n = 0;
				while (x >= 4096) {
					n += 12;
					x /= 4096;
				}
				while (x >= 2) {
					n += 1;
					x /= 2;
				}
				return n;
			}

			Number.prototype.toFixed = function (fractionDigits) {
				var f, x, s, m, e, z, j, k;

				// Test for NaN and round fractionDigits down
				f = Number(fractionDigits);
				f = f !== f ? 0 : Math.floor(f);

				if (f < 0 || f > 20) {
					throw new RangeError("Number.toFixed called with invalid number of decimals");
				}

				x = Number(this);

				// Test for NaN
				if (x !== x) {
					return "NaN";
				}

				// If it is too big or small, return the string value of the number
				if (x <= -1e21 || x >= 1e21) {
					return String(x);
				}

				s = "";

				if (x < 0) {
					s = "-";
					x = -x;
				}

				m = "0";

				if (x > 1e-21) {
					// 1e-21 < x < 1e21
					// -70 < log2(x) < 70
					e = log(x * pow(2, 69, 1)) - 69;
					z = (e < 0 ? x * pow(2, -e, 1) : x / pow(2, e, 1));
					z *= 0x10000000000000; // Math.pow(2, 52);
					e = 52 - e;

					// -18 < e < 122
					// x = z / 2 ^ e
					if (e > 0) {
						multiply(0, z);
						j = f;

						while (j >= 7) {
							multiply(1e7, 0);
							j -= 7;
						}

						multiply(pow(10, j, 1), 0);
						j = e - 1;

						while (j >= 23) {
							divide(1 << 23);
							j -= 23;
						}

						divide(1 << j);
						multiply(1, 1);
						divide(2);
						m = toString();
					} else {
						multiply(0, z);
						multiply(1 << (-e), 0);
						m = toString() + '0.00000000000000000000'.slice(2, 2 + f);
					}
				}

				if (f > 0) {
					k = m.length;

					if (k <= f) {
						m = s + '0.0000000000000000000'.slice(0, f - k + 2) + m;
					} else {
						m = s + m.slice(0, k - f) + '.' + m.slice(k - f);
					}
				} else {
					m = s + m;
				}

				return m;
			}
		}());
	}


//
// String
// ======
//


// ES5 15.5.4.14
// http://es5.github.com/#x15.5.4.14
// [bugfix, chrome]
// If separator is undefined, then the result array contains just one String,
// which is the this value (converted to a String). If limit is not undefined,
// then the output array is truncated so that it contains no more than limit
// elements.
// "0".split(undefined, 0) -> []
	if("0".split(void 0, 0).length) {
		var string_split = String.prototype.split;
		String.prototype.split = function(separator, limit) {
			if(separator === void 0 && limit === 0)return [];
			return string_split.apply(this, arguments);
		}
	}

// ECMA-262, 3rd B.2.3
// Note an ECMAScript standart, although ECMAScript 3rd Edition has a
// non-normative section suggesting uniform semantics and it should be
// normalized across all browsers
// [bugfix, IE lt 9] IE < 9 substr() with negative value not working in IE
	if("".substr && "0b".substr(-1) !== "b") {
		var string_substr = String.prototype.substr;
		/**
		 *  Get the substring of a string
		 *  @param  {integer}  start   where to start the substring
		 *  @param  {integer}  length  how many characters to return
		 *  @return {string}
		 */
		String.prototype.substr = function(start, length) {
			return string_substr.call(
				this,
				start < 0 ? ((start = this.length + start) < 0 ? 0 : start) : start,
				length
			);
		}
	}

// ES5 15.5.4.20
// http://es5.github.com/#x15.5.4.20
	var ws = "\x09\x0A\x0B\x0C\x0D\x20\xA0\u1680\u180E\u2000\u2001\u2002\u2003" +
		"\u2004\u2005\u2006\u2007\u2008\u2009\u200A\u202F\u205F\u3000\u2028" +
		"\u2029\uFEFF";
	if (!String.prototype.trim || ws.trim()) {
		// http://blog.stevenlevithan.com/archives/faster-trim-javascript
		// http://perfectionkills.com/whitespace-deviations/
		ws = "[" + ws + "]";
		var trimBeginRegexp = new RegExp("^" + ws + ws + "*"),
			trimEndRegexp = new RegExp(ws + ws + "*$");
		String.prototype.trim = function trim() {
			if (this === undefined || this === null) {
				throw new TypeError("can't convert "+this+" to object");
			}
			return String(this)
				.replace(trimBeginRegexp, "")
				.replace(trimEndRegexp, "");
		};
	}

//
// Util
// ======
//

// ES5 9.4
// http://es5.github.com/#x9.4
// http://jsperf.com/to-integer

	function toInteger(n) {
		n = +n;
		if (n !== n) { // isNaN
			n = 0;
		} else if (n !== 0 && n !== (1/0) && n !== -(1/0)) {
			n = (n > 0 || -1) * Math.floor(Math.abs(n));
		}
		return n;
	}

	function isPrimitive(input) {
		var type = typeof input;
		return (
			input === null ||
				type === "undefined" ||
				type === "boolean" ||
				type === "number" ||
				type === "string"
			);
	}

	function toPrimitive(input) {
		var val, valueOf, toString;
		if (isPrimitive(input)) {
			return input;
		}
		valueOf = input.valueOf;
		if (typeof valueOf === "function") {
			val = valueOf.call(input);
			if (isPrimitive(val)) {
				return val;
			}
		}
		toString = input.toString;
		if (typeof toString === "function") {
			val = toString.call(input);
			if (isPrimitive(val)) {
				return val;
			}
		}
		throw new TypeError();
	}

// ES5 9.9
// http://es5.github.com/#x9.9
	var toObject = function (o) {
		if (o == null) { // this matches both null and undefined
			throw new TypeError("can't convert "+o+" to object");
		}
		return Object(o);
	};

});